WASHINGTON (MEDIA GENERAL) — Republicans’ grip on power in the U.S. Senate appears to be loosening one finger at a time, as GOP candidates in blue and purple states slip below their opponents in the polls.

Democrats need to pick up four states – an achievable proposition this cycle – in order to pull even with Republicans, who currently hold 54 seats.

To keep from plunging into the abyss of insignificance, leaders on the right are plotting a way forward in the event that they become one half of a Senate split 50-50.

Majority Leader Mitch McConnell, R-Ky., has indicated that he’d support a power-sharing deal putting the two parties on equal footing.

This agreement would become official in January 2017 as the new Senate gavels into session and ratifies its operating rules for the next two years.

Power-sharing specifics

Parliamentary procedure gets a little tricky here.

The incoming vice president, who also serves as the Senate president, would break an initial 50-50 tie during the perfunctory rulemaking vote and name his party the majority.

But that majority designation would become functionally irrelevant in many ways under a bipartisan power-sharing agreement.

The last time Republicans and Democrats struck this type of compromise was in 2000, only the third such time in Senate history, reports CBS News.

Former Sen. Trent Lott, R-Miss., became majority leader with the backing of then-Vice President Dick Cheney. Lott retained some advantages of majority status, like the ability to advance legislation that stalled in committee, but agreed to share some authority with Minority Leader Tom Daschle (D-S.D.).

Based on the 2000 settlement, The Hill suggests these foundational elements in 2017 if Hillary Clinton wins the presidency:

Obtain a commitment from the Democratic leader not to change the Senate’s rules to forbid a filibuster on a Supreme Court nomination. The decision by Majority Leader Reid to change unilaterally the Senate’s rules for lower court judges requires a commitment that further erosion of the rules cannot occur in a 50-50 environment.

The Minority Leader will always have an opportunity to offer amendments to bills before the Majority Leader ‘fills the tree’ to block amendments. Majority Leader McConnell has made great strides this Congress in returning the Senate to a deliberative body and should ward against a return to the 2007-2013 era of limited floor action.

Congressional Review Act challenges will be in order. While it seems unlikely that a President Clinton would sign a CRA challenge to a new regulation issues in the dying throes of the Obama Administration, Congress should retain its authority to attack lame duck regulations.

The 50-50 deal remains in place until one party captures a 51st vote. Obtaining an actual majority by an appointment, special election or party defection should provide either party with the right to return to the normal majority-minority tradition of the Senate. However, should a seat become briefly open due to a death, incapacitation, or other short-term vacancy, the 50-50 arrangement should remain in place.

If the minority party doesn’t come to the table to solidify a deal before the first critical vote in January, they could be left out in the cold.

Key committees

Committee assignments aren’t a sexy issue, especially in a saucy campaign year like 2016, but they are hugely significant to the legislative process and presidential agendas.

Senate committee chairmen choose which bills their committees review, vote on, and send to the floor for full consideration.

If the chairman doesn’t like a proposal, it’s dead, since the majority of voting members are on their team.

The new power-sharing agreement would likely ease that stranglehold by installing an equal number of Republicans and Democrats on each committee.

If a proposal received a tied vote in committee, the majority leader would have the power to bring it to a vote in the full Senate.

This tweak could put some idling initiatives with only moderate levels of support before the full chamber, including bills aimed at immigration, Obamacare fixes, deficit reduction, and debt elimination.

The minority leader would have an opportunity to file amendments to the bill, often on contentious and otherwise unrelated subjects, before the majority party cuts off debate. If a minority-backed amendment fails to move in committee, it could be tacked on through this loophole.

Opponents could still torpedo it by launching a filibuster on the Senate floor, requiring a 60-vote supermajority for passage.

Cooperation required

All of this comes with one major caveat: McConnell signaled his openness to sharing power at a time when congressional Republicans were losing ground and GOP presidential nominee Donald Trump looked poised for failure.

If Trump wins the White House, which has become increasingly feasible, and the GOP hangs on to 50 seats in the Senate, Mike Pence, R-Ind., would make Republicans the majority and possibly jettison prior power-sharing plans.

Should either party win 51 seats, all of this cooperative chatter goes straight out the window and it’s back to acrimonious business as usual.